Hermetically sealed rotary type electric switches



Dec. 24, 1957 F. SE BASTIAN 2,317,736

HERMETICALLY SEALED ROTARY TYPE ELECTRIC SWITCHES Filed Jan. 7, 1957 IN V EN TOR. 0m kfihsrm/ H15 A TI'ORNEYS'.

Unite States Patet HERMETICALLY SEALED ROTARY TYPE ELECTRIC SWITCHES Ford SeBastian, Glen Ellyn, Ill., assignor to Midwest Controls Company, Chicago, lll., a corporation of Illinois Application January 7, 1957, Serial No. 632,759

8 Claims. (Cl. 200-168) This invention relates to new and useful improvements in hermetically sealed rotary type electric switches and has for its principal object the provision of an assembly of cooperating elements which when in assembled relation with respect to each other will provide a perfect seal with the movable parts of the switch. Such an arrangement will prevent the admission of condensation or other foreign matter into the interior of the switch.

A further and equally important object of the invention is the employment as a part of the structure of the foregoing switch, of uncured silicone of a consistency whereby it will have sufficient adhesive characteristics to adhere to the parts in engagement therewith in a manner such that when the movable parts are rotated relative to the stationary parts the sealing core provided by the silicone will have a tendency to stretch in the direction of movement of the movable parts while maintaining adhesive contact with the movable parts as well as the stationary parts, thereby resulting in a perfect seal.

Another and equally important object of the invention is the employment for hermetically sealing a switch of the character hereinafter described, of a silicone body in combination with mechanical seals whereby to assure a perfect seal.

Another important object of the invention is to provide in a switch of the class described, a seal which will Withstand temperatures of relatively low as well as relatively high degrees.

Yet another equally important object of the invention is to provide a switch hermetically sealed by an arrangement which will not bind its operating parts or interfere with the movements thereof.

Other objects will appear hereinafter.

The invention consists in the novel combination and arrangement of parts to be hereinafter described and claimed.

The invention will be best understood by reference to the accompanying drawings showing the preferred form of construction, and in which:

Fig. 1 is a side elevational view of a switch embodying my invention;

Fig. 2 is a top plan view of the same;

Fig. 3 is a sectional detail view taken substantially on line 3-3 of Fig. 1;

Fig. 4 is an enlarged fragmentary sectional detail view of the same taken on line 4-4 of Fig. 2.

The several objects of my invention are preferably accomplished by the preferred form of construction shown in the accompanying drawings.

In this connection a casing is indicated at 10. This casing is formed of .any suitable material and from this casing 10 extends a conventional conduit 11 through which conductor Wires are passed for connection with terminals 12 of a conventional electric switch 13, which switch 13 may be of the snap-action type having a push button 14 by means of which the switch 13 is actuated.

The switch 13 embodies no part of the present invention and therefore may be of any conventional type which ICC is mechanically actuated through a plunger or push button such as indicated at 14.

The top wall 15 of the casing is provided with an opening 16. Positioned in the casing 10 through the opening 16 is a housing 17 having formed at its upper end portion a hollow collar 18 of a diameter greater than the diameter of the housing 17 and abutting the top wall 15. The bottom wall 19 of the housing 17 provides an opening 18' through which a shaft 20 is journalled. Seated within the hollow collar 18 is a plug 21 which has a central opening 22 in alignment with the opening 18 and through which the shaft 20 projects. Secured to the shaft 20 on the exterior end portion thereof is a washer 23 fixed to the shaft 20 as at 24 and having its top surface serrated as at 25. Positioned between this washer 23 and the plug 21 is a sealing washer 26.

Mounted on the exterior end portion of the shaft 20 is an actuating arm 27 likewise having one surface thereof serrated for gripping engagement with the serrations 25 of the washer 23 whereby to provide an operative connection between the actuating arm 27 and the shaft 20. The arm 27 is retained on the shaft 20' by means of a lock nut assembly 27. The outer end portion of the arm 27 carries a roller 28 which is adapted to be engaged by an operating part (not shown) whereby the shaft 20 is rotated.

Within the housing 17 against the bottom Wall thereof is a cup-shaped sealing washer 29 formed of such material as will best serve the purpose. Mounted within this washer 29 is an O ring 29' and positioned upon this 0 ring 29' is a disc 30. Positioned within the housing 17 adjacent the collar 18 is a cup-shaped sealing washer 31 similar to the washer 29 but arranged in opposed relation with respect to the latter. Mounted in the cup of this washer 31 is an 0 ring 32 which bears against a disc 33. Interposed between the discs 30 and 33 and embracing the shaft 20 is an expansion spring 34 which bears the discs 30 and 33 against the 0 rings 29' and 32, which in turn are borne within their respective cups 29 and 31, thereby to provide a mechanical seat at opposite ends of the housing.

Within the housing 17 and between the discs 30 and 33 is a core of silicone. This silicone, as before stated, has the characteristic of adhering to adjacent contacting sur' faces whereby when the shaft 20 is rotated, the core will have a spiral twist without severing its contact with the surfaces contacted by the same, thus to assure a perfect seal between the housing 17 and the shaft 20.

To complete the switch structure on the exterior end portion of the shaft, there is fixedly mounted a cam 35, the heel 36 of which rides against a spring finger 37 for bearing the spring finger 37 against the plunger or push button 14 of the switch 13.

The lower end portion of the shaft 20 has a return spring 38 associated therewith. One end of this spring is connected as at 39 to the cam 35 and the other end bears as at 40 against a lug provided on the housing or casing 10 and indicated at 41.

The foregoing structure provides a hermetically sealed enclosure for an electrically actuated switch. It is especially useful under conditions in which the temperature varies from extreme low temperatures to extreme high temperatures. The parts are so related with respect to each other as to provide ready assembly and therefore economical manufacture.

While I have illustrated and described the preferred form of construction for carrying my invention into effect, this is capable of variation and modification without departing from the spirit of the invention. 1, therefore, do not wish to be limited to the precise details of construction set forth but desire to avail myself of such variations and modifications as come within the scope of the appended claims.

Having thus described my invention, what I claim as new and desire to protect by Letters Patent is:

1. A hermetically sealed enclosure for an electrically actuated switch including a casing having an opening in one wall thereof, a housing having an open end and mounted in said casing and having a collar of a diameter larger than the diameter of said opening and bearing on said wall, a plug closing said open end of the housing and having a central opening therethrough, the bottom wall of said housing being provided with an opening in alignment with the opening of the plug, a shaft journalled in said housing and passing through said openings of said plug and said bottom wall, an actuating arm on the exterior end of the shaft adjacent said plug, sealing structures arranged in said housing at opposite ends thereof and each comprising a washer and a disc and a sealing ring disposed between the washer and the disc, an expansion spring arranged between each of said sealing structures for urging the discs and the sealing ring against adjacent washers, and a body of sealing material within said housing and disposed between the sealing structures and adhesively clinging to parts in contact therewith,

2. A hermetically sealed enclosure for an electrically actuated switch including a casing having an opening in one wall thereof, a housing having an open end and mounted in said casing and having a collar of a diameter larger than the diameter of said opening and hearing on said wall, a plug closing said open end of the housing and having a central opening therethrough, the bottom wall of said housing being provided with an opening in alignment with the opening of the plug, a shaft journalled in said housing and passing through said openings of said plug and said bottom wall, an actuating arm on the exterior end of the shaft adjacent said plug, sealing structures arranged in said housing at opposite ends thereof and each comprising a washer and a disc and a sealing ring disposed between the washer and the disc, an expansion spring arranged between each of said sealing structures for urging the discs and the sealing ring against adjacent washers, and a body of sailing material within said housing and disposed between the sealing structures and adhesively clinging to parts in contact therewith, said body stretchable spirally upon rotation of the shaft relative to said housing.

3. A hermetically sealed enclosure for an electrically actuated switch including a casing having an opening in one wall thereof, a housing having an open end and mounted in said casing and having a cup-shaped collar of a diameter larger than the diameter of said opening and bearing on said wall, ,a plug mounted in said cup-shaped collar and closing said open end of the housing and having a central opening therethrough, the bottom wall of said housing being provided with an opening in alignment with the opening of the plug, a shaft journalled in said housing and passing through said openings of said plug and said bottom wall, an actuating arm on the exterior end of the shaft adjacent said plug, scaling structures arranged in said housing at opposite ends thereof and each comprising a Washer and a disc and a sealing ring disposed between the washer and the disc, an expansion spring arranged between each of said sealing structures for urging the discs and the sealing ring against adjacent washers, and a sealing core of uncured silicone arranged in said housing and disposed between the sealing structures and adhesively clinging to parts in contact therewith.

4. A hermetically sealed enclosure for an electrically actuated switch including a casing having an opening in one wall thereof, a housing having on open end and mounted in said casing and having a cup-shaped collar of a diameter larger than the diameter of said opening and bearing on said wall, a plug mounted in said cup-shaped collar and closing said open end of the housing and having a central opening therethrough, the bottom Wall of said housing being provided with an opening in alignment with the opening of the plug, a shaft journalled in said housing and passing through said openings of said plug and said bottom wall, an actuating arm on the exterior end of the shaft adjacent said plug, sealing structures arranged in said housing at opposite ends thereof and each comprising a washer and a disc and a sealing ring disposed between the washer and the disc, an expansion spring arranged between each of said sealing structures for urging the discs and the sealing ring against adjacent washers, and a sealing core of uncured silicone arranged in said housing and disposed between the sealing structures and adhesively clinging to parts in contact therewith and stretchable spirally upon rotation of the shaft relative to said housing.

5. A hermetically sealed enclosure for an electrically actuated switch including a casing having an opening in one wall thereof, a housing having an open end and mounted in said casing and having a collar of a diameter larger than the diameter of said opening and bearing on said wall, a plug closing said open end of the housing and having a central opening therethrough, the bottom wall of said housing being provided with an opening in alignment with the opening of the plug, a shaft journalled in said housing and passing through said openings of said plug and said bottom wall, an actuating arm on the exterior end of the shaft adjacent said plug, sealing structures arranged in said housing at opposite ends thereof and each comprising a washer and a cup-shaped disc and an elastic O ring embracing said shaft and mounted in said cup-shaped disc, an expansion spring arranged between each of said sealing structures for urging the discs and the sealing ring against adjacent washers, and a body of sealing material Within said housing and disposed between the sealing structures and adhesively clinging to parts in contact therewith.

6. A hermetically sealed enclosure for an electrically actuated switch including a casing having an opening in one wall thereof, a housing having an open end and mounted in said casing and having a collar of a diameter larger than the diameter of said opening and bearing on said wall, a plug closing said open end of the housing and having a central opening therethrough, the bottom wall of said housing being provided with an opening in alignment with the opening of the plug, a shaft journalled in said housing and passing through said openings of said plug and said bottom Wall, an actuating arm on the exterior end of the shaft adjacent said plug, sealing structures arranged in said housing at opposite ends thereof and each comprising a Washer and a cup-shaped disc and an elastic 0 ring embracing said shaft and mounted in said cup-shaped disc, an expansion spring arranged between each of said sealing structures for urging the discs and the sealing ring against adjacent washers, and a body of sealing material within said housing and disposed between the sealing structures and adhesively clinging to parts in contact therewith and stretchable spirally upon rotation of the shaftrelative to said housing.

7. A hermetically sealed enclosure for an electrically actuated switch including a casing having an opening in one wall thereof, a housing having an open end and mounted in said casing and having a cup-shaped collar of a diameter larger than the diameter of said opening and bearing on said wall, a plug mounted in said cupshaped collar and closing said open end of the housing and having a central opening therethrough, the bottom Wall of said housing being provided with an opening in alignment with the opening of the plug, a shaft journalled in said housing and passing through said openings of said plug and said bottom wall, an actuating arm on the exterior end of the shaft adjacent said plug, sealing structures arranged in said housing at opposite ends thereof and each comprising a washer and a cup-shaped disc and an elastic 0 ring embracing said shaft and mounted in said cup-shaped disc, an expansion spring arranged between each of said sealing structures for urging the discs and the sealing ring against adjacent washers, and a sealing core of uncured silicone arranged in said housing and disposed between the sealing structures and adhesively clinging to parts in contact therewith.

8. A hermetically sealed enclosure for an electrically actuated switch including a casing having an opening in one wall thereof, a housing having an open end and mounted in said casing and having a cup-shaped collar of a diameter larger than the diameter of said opening and bearing on said wall, a plug mounted in said cup-shaped collar and closing said open end of the housing and having :1 central opening therethrough, the bottom wall of said housing being provided with an opening in alignment with the opening of the plug, a shaft journalled in said housing and passing through said openings of said plug and said bottom wall, an actuating arm on the exterior end of the shaft adjacent said plug, sealing structures arranged in said housing at opposite ends thereof and each comprising a washer and a cup-shaped disc and an elastic 0 ring embracing said shaft and mounted in said cup-shaped disc, an expansion spring arranged be tween each of said sealing structures for urging the discs and the sealing ring against adjacent washers, and a sealing core of uncured silicone arranged in said housing and disposed between the sealing structures and adhesively clinging to parts in contact therewith and stretchable spirally upon rotation of the shaft relative: to said housing.

References Cited in the file of this patent UNITED STATES PATENTS 

